LG 37LH30FR (CHASSIS:LP91A) Service Manual ▷ View online
- 17 -
No Raster on PC Signal
Check Input source Cable And Jack
Pass
Re-soldering or
Change the defect part
Change the defect part
Pass
Check the Input/Output
Of IC100
Fail
Re-soldering or
Change the defect part,
Check RGB EDID Data
Repeat [A], & [B] Process
Pass
Check the Input/Output
Of J104
Fail
Pass
Check the Input/Output
Of IC800
Fail
Re-soldering or
Change the defect part
Pass
No Raster on COMMPONENT Signal
Check Input source
Cable And Jack
Pass
Re-soldering or
Change the defect part
Pass
Check the Input/Output
Of IC800
Fail
Re-soldering or
Change the defect part
Repeat [A], & [B] Process
Check The Input/Output
Of JK101
Fail
Pass
No Raster on HDMI Signal
Check Input source
Cable And Jack
Pass
Check the Input/Output
Of JK301, JK302, JK303
Fail
Re-soldering or
Change the defect part
Pass
Pass
Check the Input/Output
Of JK301, JK302, JK303
Fail
Re-soldering or
Change the defect part
Pass
Check the Input/Output
Of JK301, JK302, JK303
Fail
Re-soldering or
Change the defect part
Pass
Check the Input/Output
Of IC300, IC301, JK302
Fail
Re-soldering or
Change the defect part
Check HDMI EDID Data
Check HDMI EDID Data
Re-download HDCP
Pass
Pass
Check the Input/Output
Of IC800
Fail
Re-soldering or
Change the defect part
Repeat [A], & [B] Process
- 18 -
No Raster On AV (Video, S-Video)Signal
No Signal On TV(RF) Signal
Check Input source
Cable And Jack
Pass
Check Input source
Cable And Jack
Pass
Check The Input/Output
Of JK101, JK201
Pass
Re-soldering or
Change the defect part
Pass
Fail
Pass
Repeat [A], & [B] Process
Check the Input/Output
Of IC800
Fail
Re-soldering or
Change the defect part
Pass
Check The Input/Output
Of TU500
Pass
Re-soldering or
Change the defect part
Pass
Fail
Check the Input/Output
Of IC800
Fail
Re-soldering or
Change the defect part
Repeat [A], & [B] Process
No Sound
Check The Input
Sourse
Check The Input/Output
Of IC600
Re-soldering or
Change the defect part
Fail
Pass
Pass
Check The Speaker
Change Speaker
Fail
Check The Speaker Wire
Pass
Change The Source Input
Fail
- 19 -
BLOCK DIAGRAM
RG
B
_
P
C
PC
_
A
u
d
io
TV
(R
F
)
CO
M
P
1
HD
M
I1
HD
M
I2
RS
2
3
2
TX
232
C
D
riv
e
r
S
T
3232
C
T
x
/
R
x :
1
5
V
p
p
P
C
_
R
/G
/B
/
H
S
/
V
S
PC
_
A
u
d
io
_
L
/
R
:
70
0m
V
rms
MNT
_
O
U
T
:
1V
p
p
SI
D
E
_
V
:
1V
p
p
SI
D
E
_
L
/
S
ID
E
_
R
:
500mV
rms
D
D
R
2(
51
2M
B)
L
_
S
PK_
O
U
T
R
_
SP
K_
O
U
T
E
EPR
O
M
24C
0
2
Co
m
p
1
_
L
/
R
:
500mV
rms
TU
N
E
R
AV
1
_
V
IN
:
1V
p
p
A
V
11_
L
IN
/
R
IN
:
50
0m
V
rms
PW
M
N
T
P
3
100L
MNT
_
O
U
T
MNT
_
LO
U
T
/
R
O
U
T
:
5
00m
V
rm
s
AV
2
(S
id
e
A
V
)
MAI
N
S
C
AL
E
R
T
X
D
/
R
X
D
:
5V
Di
g
it
a
l
CO
M
P
1
_
Y
/
P
b
/
P
r
:
1/
0.
7
V
p
p
CO
M
P
2
_
Y
/
P
b
/
P
r
: 1
/
0.
7
V
p
p
IR
H
D
MI
_
D
AT
A_
1
H
D
MI
_
D
AT
A_
2
H
D
M
I1
_
SC
L
/
SD
A
OUT
_
E
_
T
X
_
C
L
K
O
U
T_
E
_
TX
_
E
O
U
T_
E
_
TX
_
D
O
U
T_
E
_
TX
_
C
O
U
T_
E
_
TX
_
B
O
U
T_
E
_
TX
_
A
TU
_
M
A
IN
S I
F
CO
M
P
1
_
Y
/
P
b
/
P
r
1/
0
.7
V
p
p
AV
1
_
V
IN
PC
_
A
u
d
io
_
L
/
R
CO
M
P
1
_
L
IN
/
R
IN
L_
C
H
R_C
H
LV
DS
co
nnec
tor
TU
_
M
A
IN
SU
B
_
SC
L
SD
A
E
EPR
O
M
24C
0
2
E
EPR
O
M
24C
0
2
SI
F
AV
1
_
LI
N/
R
IN
MNT
_
L/
R
O
U
T
AV
1
MN
T
_
O
U
T
Co
m
p
2
_
L
/
R
:
500mV
rms
CO
M
P
2
_
Y
/
P
b
/
:
1/
0
.7
V
p
p
CO
M
P
2
_
L
IN
/
R
IN
CO
M
P
2
OUT
_
O
_
T
X
_
C
L
K
O
U
T_
O
_
TX
_
E
O
U
T_
O
_
TX
_
D
O
U
T_
O
_
TX
_
C
O
U
T_
O
_
TX
_
B
O
U
T_
O
_
TX
_
A
PC
_
R
/
G
/
B
/
H
S
/
V
S
H
D
M
2
_
S
CL
/
S
DA
P
C
_
S
CL
/
S
DA
MNT
_
V
O
U
T
AV
2
_
V
IN
AV
2
_
LI
N/
R
IN
II
S
_
O
U
T
US
B
US
B
_
D
N
/
P
N
AU
D
IO
AMP
H
D
M
I3
_
SC
L
/
SD
A
E
EPR
O
M
24C
0
2
H
D
MI
_
D
AT
A_
3
TM
D
S
TM
D
S
TM
D
S
HD
M
I3
US
B
Fo
r D
/
L
E
E
PR
O
M
(2
5
6
K)
Se
ri
a
l F
la
s
h
(8
M
B
y
te
)
RG
B
_
P
C
PC
_
A
u
d
io
TV
(R
F
)
CO
M
P
1
HD
M
I1
HD
M
I2
RS
2
3
2
TX
232
C
D
riv
e
r
S
T
3232
C
–
P
C
_
R
/G
/B
/
H
S
/
V
S
PC
_
A
u
d
io
_
L
/
R
:
70
0m
V
rms
MNT
_
O
U
T
:
1V
p
p
SI
D
E
_
V
:
1V
p
p
SI
D
E
_
L
/
S
ID
E
_
R
:
500mV
rms
D
D
R
2(
51
2M
B)
E
EPR
O
M
24C
0
2
Co
m
p
1
_
L
/
R
:
500mV
rms
TU
N
E
R
AV
1
_
V
IN
:
1V
p
p
A
V
11_
L
IN
/
R
IN
:
50
0m
V
rms
PW
M
N
T
P
3
100L
MNT
_
O
U
T
MNT
_
LO
U
T
/
R
O
U
T
:
5
00m
V
rm
s
AV
2
(S
id
e
A
V
)
MAI
N
S
C
AL
E
R
T
X
D
/
R
X
D
:
5V
Di
g
it
a
l
CO
M
P
1
_
Y
/
P
b
/
P
r
:
1/
0.
7
V
p
p
CO
M
P
2
_
Y
/
P
b
/
P
r
: 1
/
0.
7
V
p
p
H
D
MI
_
D
AT
A_
1
H
D
MI
_
D
AT
A_
2
_
OUT
_
E
_
T
X
_
C
L
K
–
O
U
T_
E
_
TX
_
–
O
U
T_
E
_
TX
_
–
O
U
T_
E
_
TX
_
C
–
O
U
T_
E
_
TX
_
B
–
O
U
T_
E
_
TX
_
A
–
TU
_
M
A
IN
S I
F
CO
M
P
1
_
Y
/
P
b
/
P
:
1/
0
.7
V
p
p
AV
1
_
V
IN
PC
_
A
u
d
io
_
L
/
R
CO
M
P
1
_
L
IN
/
R
IN
L_
C
H
R_C
H
LV
DS
co
nnec
tor
TU
_
M
A
IN
/
E
EPR
O
M
24C
0
2
E
EPR
O
M
24C
0
2
SI
F
AV
1
_
LI
N/
R
IN
MNT
_
L/
R
O
U
T
AV
1
MN
T
_
O
U
T
Co
m
p
2
_
L
/
R
:
500mV
rms
CO
M
P
2
_
Y
/
P
b
/P
r
1/
0
.7
V
p
p
CO
M
P
2
_
L
IN
/
R
IN
CO
M
P
2
OUT
_
O
_
T
X
_
C
–
O
U
T_
O
_
TX
_
E
–
O
U
T_
O
_
TX
_
D
–
O
U
T_
O
_
TX
_
C
–
O
U
T_
O
_
TX
_
B
–
O
U
T_
O
_
TX
_
A
–
PC
_
R
/
G
/
B
/
H
S
/
V
S
P
C
_
S
CL
/
S
DA
P
C
_
S
CL
/
S
DA
MNT
_
V
O
U
T
AV
2
_
V
IN
AV
2
_
LI
N/
R
IN
II
S
_
O
U
T
US
B
US
B
_
D
N
/
P
N
AU
D
IO
AMP
H
D
M
I3
_
SC
L
/
SD
A
H
D
M
I3
_
SC
L
/
SD
A
E
EPR
O
M
24C
0
2
H
D
MI
_
D
AT
A_
3
TM
D
S
TM
D
S
TM
D
S
HD
M
I3
US
B
Fo
r D
/
L
E
E
PR
O
M
(2
5
6
K)
Se
ri
a
l F
la
s
h
(8
M
B
y
te
)
- 20 -
300
200
830
822
821
510
120
500
310
900
550
530
540
800
810
820
520
400
200T
A2
LV1
A10
EXPLODED VIEW
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These
parts are identified by in the Schematic Diagram and EXPLODED VIEW.
It is essential that these special safety parts should be replaced with the same components as
recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
parts are identified by in the Schematic Diagram and EXPLODED VIEW.
It is essential that these special safety parts should be replaced with the same components as
recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
IMPORTANT SAFETY NOTICE
Click on the first or last page to see other 37LH30FR (CHASSIS:LP91A) service manuals if exist.